Regulations

Majority of the world still permits the use of chrysotile following safe use guidelines. For example, in the US, the regulations for amphibole asbestos and chrysotile are different. In Canada, there are strict workplace exposure limits for asbestos and emissions into the environment from mining are regulated. Russia permits concentrations of chrysotile of no more than 2 milligrams per cubic metre.

The case of Thailand

The import, usage and storage of asbestos is controlled by the Department of Industrial Work regulates and controls import, use, and storage of asbestos. In addition, the Labour Protection Law of the Ministry of Labour also provided regulations regarding asbestos. This provision indicates an occupational exposure standard level for asbestos in order to protect health of workers.

Crocidolite has been banned under the Hazardous Substance Act B.E. 2535 due to being a highly toxic chemical.

Clause 5: The employer is prohibited to allow the worker, works in the area which has higher quantity of dust/fibre in the air, as shown in table 4, throughout normal working period.

Clause 6: The working area which is exposed to high dose of chemical materials, a controlled room or building should be provided for special isolation.

Clause 7: In the working area which is exposed to higher quantity of dust/fibre than Table 4, and the employer can not improve the said working condition, the employer have to provide the standard personal safety device for all workers.

2. Table 4

The Threshold Limit Value (TLV) = 5 fibres/cc

Standard TLV of airborne fibre in working condition

Ministry Of Natural Resources & Environment (MoN&E)

Safety Instruction on working with Chemical Materials, including asbestos

Information on hazard, house-keeping, and disposal, etc.

Regulations in North America and EuropeUntil recently, leading regulatory agencies did not distinguish the differences between amphibole and chrysotile types of asbestos in their policy. But with the evidence of up to date scientific and epidemiological studies these agencies have begun to revise approaches to asbestos policy.

Two leading countries, the United States and the United Kingdom have been revising their positions and regulations concerning the industrial use of chrysotile.

In 2001, Environmental Protection Agency (EPA) has started to revise their outdated U.S. EPA model for lung cancer and mesothelioma based primarily on a document completed in 1986 (U.S. EPA 1986). The main feature of the last U.S. EPA model for lung cancer and mesothelioma is that this model did not take into account differences in type of asbestos fiber. In other words, according to this model, all fiber types have equal potency of causing cancer.

In 2003, scientists D. Wayne Berman, Aeolus, Inc. and Kenny S. Crump, Environ Corporation prepared a document by request of U.S. EPA. The final draft of this document is called “Final Draft: Technical Support Document For A Protocol To Assess Asbestos-Related Risk”.

This document stated that:"The approach currently employed at the U.S. EPA to evaluate asbestos-related risks (IRIS 1988) is based primarily on a document completed in 1986 (U.S. EPA 1986) and has not been changed substantially in the past 15 years, despite substantial improvements in asbestos measurement techniques and in the understanding of the manner in which asbestos exposure contributes to disease. Therefore, this document provides an overview and evaluation of the more recent studies and presents proposed modifications to the protocol for assessing asbestos-related risks that can be justified based on the more recent work."

AND:"Results in Table 7-17 also differentiate between the potency of chrysotile and amphibole for both lung cancer and mesothelioma. Amphibole is estimated as being about four times as potent as chrysotile for lung cancer (although the difference is not significant) and about 800 times as potent as chrysotile for mesothelioma (a highly significant difference). Moreover, the data are consistent with the hypothesis that chrysotile has zero potency toward the induction of mesothelioma."

Based on this document, EPA is going to change its outdated model for lung cancer and mesothelioma in recognition of the huge difference between chrysotile and amphiboles. The agency will have two different formulas describing exposure to chrysotile and to amphibole asbestos instead of one.

In June 2006, Kevin Walkin and Geoff Lloyd under the lead of Giles Denham, a board member, prepared a risk assessment paper for the Health and Safety Executive (HSE) of the United Kingdom. This document is called "A Comparison of the Risks from Different Materials Containing Asbestos."

HSE agreed that there should be a risk-based approach to the licensing of asbestos, with licensing reserved for high risk products and processes.

The document stated that: "The epidemiological evidence from asbestos workers and well-conducted animal tests shows that while all types of asbestos share the same hazards (e.g. the potential of an early death from lung cancer, asbestosis and mesothelioma) they have varying degrees of risk (the likelihood that death from one of the hazards will occur). The relative risk from the same level of exposure but to different asbestos fibre types is shown in figure 1 (see graphics on page 6,7,8,9 and 10 of present document) as derived by Hodgson and Darnton, 2000. The relative risk from crocidolite asbestos is some 500 times greater than chrysotile asbestos and the relative risk from amosite asbestos is 100 times greater than chrysotile asbestos. This means that the type/s of asbestos in the product are particularly significant when assessing risk."

"The results for the lifetime risk in figure 6 for 40 years exposure from the age of 20 represent a worst case continuous exposure situation. The highest risk is by far the one caused by sprays and other insulation groups (risk 11,419 per 100,000) and AIB (risk 1,642 per 100,000). These are the two licensed groups. The next highest group is the jointings and packings, (risk 55 per 100,000) but as the risk is mainly associated with the amount of crocidolite and amosite asbestos products remaining and many gaskets and packings are replaced during routine maintenance and servicing, this is likely to be an overestimate of the remaining risk. Some of the products in this group if present for thermal insulation would be regarded as licensed materials."

"All the other groups are essentially non-licensed products (textured coating –i.e. some fillers and reinforcements are currently licensed). It can be seen that the nonlicensed product groups have an over a thousand times lower risk than licensed sprays and other insulations group and over a hundred times lower than the licensed AIB and millboard groups."

The same exposure situation was used to calculate the annual risk of death based on an average survival age of 80. See figure below:

Figure 1: Annual risk of death per million based on 10% of time actively removing ACMs from age 20 to 40 years with limited controls: no RPE

"The more detailed assessment by product group showed again that by far the highest risk resides in the two product groups that contain licensed asbestos materials. The next highest risk group is jointings and packings, which contain some materials that would in some situations be regarded as licensed. The calculated annual risk of death for 40 years of exposure from age 20 are compared to the risk from other workplace fatalities in figure 9 (and HSE statistics 2004) and the lower rates for non-licensed materials are compared to public / societal risks in figure 10 (see R2P2 (2001) and Royal Society, 1981). Again, it is important to remember that the estimated asbestos risk for a population of frequently exposed workers has been based on the use of limited controls and no use of RPE with 40-year duration of exposure and must be regarded as an upper estimate."

Figure 2: Comparisons of textured coating an asbest cement product group annual risk of death per million to other public risks. (Asbestos risk based on 10% of time actively removing ACMs from age 20 to 40 years with limited controls and no RPE)